Strange noises in Botany Bay

[fran1mat]

Hello,

Now, I heard something today that I cannot explain. I wasn't just 'hearing things' as my wife has since suggested. I had a mate on board with me and he and I stood in amazement for at leat 20 seconds trying to work out what the noise was.

Today, just after 6am, my mate and I were fishing just off the groins at Kurnell. We mentioned how peaceful it was without the passenger jets coming into land over our heads. No sooner had this been mentioned and in they came.

After the second plane had passed over us and had well and truely landed, a small low cloud passed right over the top of us, and that is when things got weird (please keep in mind the cloud was above us and not on the same line the passenger jets were coming in on).

For about 20 seconds we listened to what I can only describe as a high pitched sound bounce around seemingly between us and the low passing cloud. The sound moved around, left to right and up and down, but seemingly was 'attached' in someway to the cloud. The sound appeared to be between the water and the cloud. The best way to describe the sound is like someone had shrunk an F1-11 and it was screaming around above us, of air moving really fast and hard.

There was definately no other aircraft in the area.

Now, I know what you guys are currently thinking - this bloke is a crackpot. Next he will tell us he was abducted by an alien and probed inappropriately.

Please believe me, I am a rational and reasonable person. I just cannot for the life of me work out what the noise was. My mate is stumped as well. I had my bloody brand new iPhone in my pocket too, but I was so amazed by the sounds, I just didn't think to get it out.

So, if anyone has heard this before, if you think you might know what it is, or if you were the guy in the pedalpowered Hobie kayak or the other bloke in the runabout just off Bonner Point at 6am this morning, let me know if you heard it.

Matt

Edited January 8, 2011 by catch'n'release

[michaelrdoyle@gmail.com]

You;ll be hearing the "wingtip vortex" or "vortex winds" - basically - as the plan passes, the wings create vortexes, that you end up hearing about 30 seconds to 1 minute after the plane leaves - it is very very very freaky.

I use to go running at night and the running path went past the end of one of the runways - often the noise would occur heaps after the plane goes - it's like a rushing of wind all around you, you can even feel it, and see it flatten the grass - but no airplane can be seen! It's very freaky. But cool.

Mike

[fran1mat]

I think you are spot on Mike, I just found this on a 'plane fanciers' website from 1999 -

If conditions are right, you can see the vortex contrails trailing behind the aircraft. I noticed the sound also, but put the sound and these vortexes together when spotting one day. I appears to me that you are hearing the vortexes swirl and collapse on themselves.

[musty]

"Sound" has very unusual behaviors. I remember freaking out the 1st time i was anchored up night fishing at port kembla breakwall as the tug boats worked to push a cargo ship into port approximatley 100m away. The rattlings and banging vibration on the bottom of my aluminium hull had me concerned- i was checking the tinny for cracks, leaks, and generally freaking out, only for it to cut out once the tugs got further away and cut their engines. Sound and vibrations really do behave very differently depending on their environment.

Interesting post mate

Musty

[johnv]

wow,, now i know what those sounds are after read this post. I thought it might have been a whale making these noises in the bay we actually drove around in the bay for 15minutes looking around but now reading this i know what it was thank guys.

cheers john

[Guest Aussie007]

Now, I know what you guys are currently thinking - this bloke is a crackpot. Next he will tell us he was abducted by an alien and probed inappropriately.

classic

[spizza]

You;ll be hearing the "wingtip vortex" or "vortex winds" - basically - as the plan passes, the wings create vortexes, that you end up hearing about 30 seconds to 1 minute after the plane leaves - it is very very very freaky.

I use to go running at night and the running path went past the end of one of the runways - often the noise would occur heaps after the plane goes - it's like a rushing of wind all around you, you can even feel it, and see it flatten the grass - but no airplane can be seen! It's very freaky. But cool.

Mike

Very true, I have also experienced this regularly off the runways fishing of a boat and my kayak and after a plane has hovered over the top for landing etc...

[Smitty]

You;ll be hearing the "wingtip vortex" or "vortex winds" - basically - as the plan passes, the wings create vortexes, that you end up hearing about 30 seconds to 1 minute after the plane leaves - it is very very very freaky.

I use to go running at night and the running path went past the end of one of the runways - often the noise would occur heaps after the plane goes - it's like a rushing of wind all around you, you can even feel it, and see it flatten the grass - but no airplane can be seen! It's very freaky. But cool.

Mike

Yep, I've heard these whilst fishing in the Cookes when the planes are landing from the west. They do sound freaky but VERY cool!!!!

[winfield]

Hello,

Now, I heard something today that I cannot explain. I wasn't just 'hearing things' as my wife has since suggested. I had a mate on board with me and he and I stood in amazement for at leat 20 seconds trying to work out what the noise was.

Today, just after 6am, my mate and I were fishing just off the groins at Kurnell. We mentioned how peaceful it was without the passenger jets coming into land over our heads. No sooner had this been mentioned and in they came.

After the second plane had passed over us and had well and truely landed, a small low cloud passed right over the top of us, and that is when things got weird (please keep in mind the cloud was above us and not on the same line the passenger jets were coming in on).

For about 20 seconds we listened to what I can only describe as a high pitched sound bounce around seemingly between us and the low passing cloud. The sound moved around, left to right and up and down, but seemingly was 'attached' in someway to the cloud. The sound appeared to be between the water and the cloud. The best way to describe the sound is like someone had shrunk an F1-11 and it was screaming around above us, of air moving really fast and hard.

There was definately no other aircraft in the area.

Now, I know what you guys are currently thinking - this bloke is a crackpot. Next he will tell us he was abducted by an alien and probed inappropriately.

Please believe me, I am a rational and reasonable person. I just cannot for the life of me work out what the noise was. My mate is stumped as well. I had my bloody brand new iPhone in my pocket too, but I was so amazed by the sounds, I just didn't think to get it out.

So, if anyone has heard this before, if you think you might know what it is, or if you were the guy in the pedalpowered Hobie kayak or the other bloke in the runabout just off Bonner Point at 6am this morning, let me know if you heard it.

Matt

yeah i get this all the time, i live out at leichhardt so when a southerly blows we are the flight path.I find only the older vergin plane do it,think it6s got somthing to do with the wingtip stabilizers.

[Gribble]

Wake vortexes are a by-product of lift production from the wing. Its essentially the same thing as the wake waves from behind your boat. Its the higher pressure from under the wing making its way back over and top into the lower pressure air, thats where the vortex comes from.

Thats a painfully simplistic way of explaining it. You cant make a plane fly without making a wake vortex the same as you cant move your boat through water without making a wake wave(s). The displaced water wants to return to where you disturbed it from. Its Newton's equal and opposite reaction.

If you need a better explanation there are a million videos on youtube that explain wake vortex and why its really bad for little planes that private pilots fly. If you ever see a large plane fly into or out of cloud see if you can see the vortex in the cloud, you will understand why it might be bad for a smaller plane.

[Rafinx]

Found a good one

[GCC]

Was that a day when we had storms?

Just thinking that with the noise bouncing around etc whether it might have been static building up?

Also wondering if you were being targeted for a lightning bolt?

My two cents worth anyway.

[GCC]

Umm, just listened to the YouTube video...

I'll retract my last post.

[fran1mat]

Well done folks.

My mate and I discussed it a bit more, the plane that we think the sounds were from actually had vapour trails coming off the wingtips as it passed by us, not sure if that had any bearing.

Rafinx, that is exactly what we heard mate.

I have cancelled my appointment with the shrink now and feel I can safely venture back onto the Bay.

Matt

[Rafinx]

I didnt know what you meant untill I looked it up and then im like ive heard that before >.>

[Kevsta]

My in-laws live in a house under the flight path and I hear that noise on the odd occassion and when I do, I'm looking toward the sky to try and spot the air force fighter jet, but could never see any aircraft.

Thanks for clearing that up for me.